BMO Financial & Investment ServicesBanks & Credit Unions Visit Website 790 N. Water Street Milwaukee, WI 53202 Facebook Twitter About Map About Established in 1882 as Harris Bank, and owned by BMO Financial Group since 1984, BMO Harris Bank has grown to become one of the largest banks in the Midwest serving personal, commercial and affluent customers. What's Nearby? Distance: 5 10 15 20 25 50 mi.